JPS62146296A - Plated product having cationic electrodeposited acrylic paint film - Google Patents

Abstract

PURPOSE:To effectively improve the corrosion preventing property of a plated product without deteriorating the appearance or color tone by neutralizing a specified vinyl copolymer with an org. acid to obtain a water soluble acrylic paint for cationic electrodeposition and by forming an electrodeposited paint film on the plated product with the paint. CONSTITUTION:An ethylenic unsatd. monomer having an aminimido group represented by the formula (where R1 is H or methyl, each of R2 and R3 is 1-4C alkyl and R4 is H, alkyl, hydroxyalkyl, cycloalkyl, aryl, aralkyl or alkaryl) is copolymerized with an ethylenic unsatd. monomer having an amino group, a hydroxyalkyl deriv. or acrylic acid and alpha,beta-ethylenic unsatd. monomer such as alkyl acrylate in a water soluble org. solvent. The resulting vinyl copoly mer is neutralized with an org. acid to obtain a water soluble or water dispersi ble acrylic paint for cationic electordeposition. An electrodeposited paint film of a prescribed thickness is formed on the plated surface of a prescribed plated product with the paint.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a plated product having a novel acrylic cationic electrodeposited coating, which effectively improves corrosion resistance without impairing the appearance and color tone of the plating. The present invention also relates to plated products with excellent design effects.

(Prior art and its problems) Copper-plated or copper alloy-plated products have been widely used for tableware, lighting equipment, etc., but if the plated surface is left untreated, it is easily oxidized in the air, and its beautiful appearance is lost. It has been observed that the color tone becomes blackish. In addition, greasy plating is also used for jewelry and ornaments, but it is a typical plated product that easily discolors, and it is well known that it forms black silver sulfide and discolors in a sulfuric atmosphere. This is where I am. Furthermore, even nickel-plated products gradually discolor in the air and lose their luster. Further, corrosion is likely to occur due to electrolytic corrosion in the presence of moisture or electrolytes, and recently, corrosion resistance against sweat and fingerprints has also been discussed.

By the way, plating treatment for various products is a surface treatment with excellent gloss, color tone, and corrosion resistance, but it is inferior to other surface treatments such as dyed alumite and painting, especially when it comes to freedom of color tone. As is well known. However, plating is unrivaled as a means of achieving a smoothing effect and specular gloss, and if a variety of color tones are added to this gloss, it becomes a surface treatment method rich in unprecedented design.

For this reason, conventionally, a transparent or transparent colored coating film is formed on the plated surface of plated products, and its shielding effect improves corrosion resistance without impairing the appearance or color tone of the plated product. Countermeasures are being considered to improve the design, but with traditional mechanical painting methods such as spraying, it is difficult to obtain a uniform coating, and it is difficult to obtain a uniform coating film due to the adhesion of dirt, dust, etc. It has been difficult to take full advantage of the color tone of the plating, as it causes a decrease in gloss and gives a thick paint feel to the coating.

On the other hand, electrodeposition coating (as is well known) involves placing a water-soluble paint or a water-dispersible paint in a paint bath, dipping the metal object in this, and placing the object and the bath tank or This is a method in which a direct current is passed through one of the electrodes as an anode and the other as a cathode to form a coating film on the surface of the object, similar to electroplating.

The case where such a coated object is used as an anode is called an anion type.
When used as a cathode, it is called a cation type. Also,
The paints used for such electrodeposition coatings exist as ions in the paint bath, and are called anionic paints or cationic paints depending on the type of ions. Therefore, by dispersing organic pigments with good weather resistance in such electrodeposition paints and electrodepositing them, the pigments are eutectoid in the paint film, and then melted by baking, giving a glossy appearance to the product surface. It is possible to give a different design effect.

Also, regarding clear coating, the coating film obtained by electrodeposition does not sag, is uniform, and has good transparency, making it possible to take advantage of the original color tone of the plating. From these points, it can be said that an electrodeposition coating is desirable as a coating film to be formed on the plated surface of a plated product.

By the way, in the electrodeposition paint that is applied on the plated surface of plated products, the paint resin that makes up the paint must (a) have good transparency in order to take advantage of the color of the plating, and (b) be coated on the plated surface. It is required that the paint film formed on the acrylic film does not yellow or become discolored due to baking, and (c) it has good weather resistance.From these points of view, acrylic Electrodeposition paints based on this type are considered to be the most suitable electrodeposition paints.

However, in the case of acrylic electrodeposition paints, especially when they are anionic, the material to be coated becomes an anode, and the material (plated film) is eluted (Me
-*Me""+n e-), which may cause problems such as discoloration and poor appearance. For example, plated products that are easily affected by discoloration and poor appearance,
There are silver plating and its alloy plating products, copper plating and its alloy plating products, black nickel plating (Ni-Zn) products, chrome plating products, etc. On the other hand, in the case of cationic type acrylic electrodeposition paints, the above-mentioned plating products can be applied because the elution of the material is difficult, but the conventional cationic type electrodeposition paints General epoxy-urethane.

Epoxy-polyamide-based paints include the above (a) to (c).
None of the conditions were satisfied.

(Solution Means) Here, the present invention was made against the background of the above circumstances, and while it is possible to effectively improve the corrosion resistance without impairing the appearance and color tone of the plating, it is also rich in design. The purpose is to provide a plated product having an acrylic cation type electrodeposited coating film with excellent performance such as transparency and weather resistance, which provides a soldered surface. Formula: %Formula% (However, R4 is a hydrogen atom or a methyl group, R2 and R3 are each an alkyl group having 1 to 4 carbon atoms, and R
4 is a hydrogen atom, an alkyl group, a hydroxyalkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkaryl group); (b) an ethylenically unsaturated monomer having an amine imide group; an ethylenically unsaturated monomer; (C) one or more hydroxyalkyl or amide or amide derivatives of acrylic acid or methacrylic acid; and (d) an alkyl ester of acrylic acid and methacrylic acid and an aromatic vinyl monomer. A vinyl copolymer obtained by copolymerizing at least one α,β-ethylenically unsaturated monomer selected from the group in a water-soluble organic solvent, or a non-yellowing vinyl copolymer. An organic acid and/or a curing agent that reacts with the vinyl copolymer and/or the non-yellowing block isocyanate compound to cure the vinyl copolymer and/or the non-yellowing block isocyanate compound. Alternatively, by adding mineral acid to neutralize the vinyl copolymer and making it water-soluble or water-dispersible, an electrodeposition coating film made of an acrylic cation type electrodeposition paint is applied to a predetermined plating layer. The reason is that it is formed at a predetermined thickness on the plated surface of the product.

Thus, in the present invention, an ethylenically unsaturated monomer (component a) having an amine imide group represented by the above structural formula is used, and a predetermined acrylic vinyl monomer (components b to d) is used. A characteristic feature is that a vinyl copolymer obtained by copolymerizing with is used as the main resin of electrodeposition paint for plated products, and such a copolymer has a specified amine imide group in its side chain. We have it. When the paint adhered to the surface of the object to be coated (plated product) is heated and baked to form the desired coating film, this amine imide group is combined with isocyanate and amine as shown in the formula below. R′ and the isocyanate groups hanging from the main chain of the copolymer react with hydroxyl groups present in the copolymer, other hydroxyl compounds, compounds having active hydrogen such as amine compounds, Cross-linking is induced, which causes
The durability of the formed coating film, such as its solvent resistance, is effectively improved.

By the way, the ethylenically unsaturated monomer (component a) having an amine imide group represented by the above structural formula used in the present invention can undergo addition polymerization, as disclosed in Japanese Patent Publication No. 34686/1986. Generally, R4 in the above structural formula is a hydrogen atom, a phenyl group, or an alkyl group, especially a lower (
A compound having a C+ to C4) alkyl group is preferably used. More specifically, dimethyl-2-hydroxypropylamine methacrylimide and dimethyl-
(2-hydroxy-3-butoxypropyl)amine methacrylimide, dimethyl-1,2-dihydroxypropylamine methacrylimide, dimethyl-2-hydroxy-1-phenylpropylamine methacrylimide,
Dimethyl-2-hydroxy-1-cyclohexylpropylamine methacrylimide and the like can be mentioned.

As mentioned above, the amine imide group-containing component (a) functions as a curing component in the electrodeposition coating, and is generally used in a copolymerization amount of 10 to 40% by weight. In addition, the amount of copolymerization is
When it is lower than 10% by weight, the crosslinking density becomes small,
In addition, there is a risk that performance such as solvent resistance of the electrodeposited coating may deteriorate.On the other hand, if the copolymerization amount exceeds 40%, OIT
This causes problems such as a decrease in the boiling water resistance of the coating film.

In addition, the ethylenically unsaturated monomer having an amino group as the component monomer (b) is an essential component in ensuring the water dispersibility of the obtained copolymer, and is generally used in a proportion of 3 to 15%. They will be copolymerized in the process. In addition, if the copolymerization amount is lower than 3%, water dispersibility will deteriorate, bath stability will deteriorate,
Problems such as deterioration in the appearance of the coating film occur, and on the other hand, if the amount of copolymerization exceeds 15% by weight, problems such as a decrease in the acid resistance of the coating film occur. Examples of such ethylenically unsaturated monomers having an amino group include dimethylamine ethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylaminopropyl acrylate, dimethylamine propyl methacrylate, etc. There is.

Furthermore, according to the present invention, the hydroxyfurkyl or amide or amide derivative of acrylic acid or methacrylic acid, which is the component C1, functions as a curing component and also partially plays the role of imparting water dispersibility. ,
For example, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monoacrylate, and One or more of methacrylate, acrylamide, methylol acrylamide, methacrylamide, methylol methacrylamide, alkoxymethylol methacrylamide, diacetone acrylamide, diacetone methacrylamide, etc. will be used. The copolymerization amount of component (C) monomer is generally about 10 to 40% by weight; if the copolymerization ratio is too small, the water dispersibility of the paint may decrease or the appearance of the paint film may deteriorate. If the copolymerization ratio exceeds 40% by weight, problems such as a decrease in alkali resistance occur.

Furthermore, the fourth component (dl component monomer), which is copolymerized with the (al component monomer, (bl component monomer) and (C1 component monomer), consists of alkyl esters of acrylic acid and methacrylic acid and an aromatic vinyl monomer. At least one α,β-ethylenically unsaturated monomer selected from the group, and these monomers harden the formed coating film and improve its chemical resistance such as salt water resistance. This (di component monomer is the above-mentioned (al, (b) and (C)
) In addition to the usage ratio of component monomers, the total amount is 100%
Generally, the copolymerization ratio is between 40 and 80.
It is used in an amount of about 50% by weight, preferably 50 to 70% by weight.

If the copolymerization ratio of this (d+ component monomer) is too low, the chemical resistance of the coating film will decrease, while if the copolymerization ratio is too high, the adhesion, impact resistance, and Problems such as a decrease in weather resistance etc. will occur.In particular, it is desirable that the component (d) monomer is selected so as to contain at least an aromatic vinyl monomer. Such aromatic vinyl)Lt-7- is used in a range of 5 to 30ffi1%.

In addition, (alkyl esters of acrylic acid and methacrylic acid as di component monomers include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and ethyl methacrylate. , isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, lauryl methacrylate, etc., and aromatic vinyl monomers include styrene, vinyltoluene, etc.

Further, such copolymers consisting of (a) to (dl component monomers) are used to form a predetermined electrodeposition coating material with an appropriate molecular weight, but generally the weight average molecular weight is 5,000 to 60,000. Those with a weight average molecular weight of 50 or less are preferably used.
If the weight average molecular weight is lower than 00, the performance such as solvent resistance and boiling water resistance will deteriorate, and the water dispersibility of the curing agent will deteriorate.
This results in problems such as poor uniform electrodeposition, reduced gloss, and increased likelihood of skin roughness.

In the copolymerization of component monomers (a) to (d), water-soluble organic solvents such as methanol, ethanol, propatool, isopropanol, butanol, isobutanol, L-butanol, etc. are used as the polymerization medium. Furfuryl alcohol, tetrahydrofurfuryl alcohol, dioxane, Te1-rahydrofuran, methyl lactate, ethyl lactate, γ-butyrolactone, ethylene glycol and its monoether (cellosolve), diethylene glycol and its monoether, triethylene glycol, propylene glycol, dimethyl formamide,
There are dimethylacetamide, sulfolane, dimethylsulfoxide, etc., and in such water-soluble organic solvents,
Copolymerization is allowed to proceed in the presence of a suitable radical polymerization catalyst (addition polymerization catalyst) such as azobisisobutyronitrile or benzoyl peroxide. In addition, this copolymerization is
Generally, it will be carried out at a temperature of 0 to 150°C, preferably 30 to 100°C, for 10 minutes to 24 hours, preferably 30 minutes to 6 hours.

The solution of the vinyl copolymer consisting of components (a) to (dl) obtained in this way is mixed with an appropriate non-yellowing block isocyanate compound, or without being mixed with an organic acid. and/or a mineral acid is added to neutralize the vinyl copolymer and make it water-soluble or water-dispersible in the form of a neutralized salt, thus forming the desired acrylic cation type. This results in the formation of an electrodeposition paint.

The non-yellowing block isocyanate compound blended into the vinyl copolymer is generally used as a crosslinking agent, and in the present invention, it is blended as necessary. It is usually blended in a proportion of about 5 to 40% by weight, preferably about 15 to 30% by weight of the total solid content after blending. In addition, if the amount of this non-yellowing blocked isocyanate compound is too large, it becomes difficult to make it water-soluble.

In addition, this non-yellowing blocked isocyanate compound is
Preferably, aliphatic or cycloaliphatic isocyanate compounds having two or more isocyanate groups, such as hexamethylene diisocyanate, lysine diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), methylcyclohexane-2,4(2,6 )−
Diisocyanate, 1,3-(isocyanatomethyl)
Compounds such as cyclohexane, isophorone diisocyanate, trimethylhexamethylene diisocyanate, dimer acid diisocyanate, etc., in which substantially all of their isocyanate groups are blocked with a suitable blocking agent, such as a -hydric alcohol.

In addition, when producing the acrylic cationic electrodeposition coating composition according to the present invention, a curing agent that reacts with the vinyl copolymer and/or the non-yellowing block isocyanate compound to cure them is optionally used. is blended. The amount of this curing agent to be blended is generally about 10 to 30% by weight based on the total solid content after blending. And as this hardening agent,
Specifically, there are amine compounds containing two or more amine groups having activated hydrogen, polyamine resins, and known polyol resins containing hydroxyl groups such as acrylic, epoxy, alkyd, polyester, or polyol resins. .

Furthermore, the acrylic cationic electrodeposition paint according to the present invention may optionally contain ethylene alcohols, diethylene monoalkyl ethers, aliphatic alcohols, acetic esters, and ketones as auxiliary solvents that help water-solubilize the paint components. In some cases, a water-soluble solvent such as the following may be further added and blended.

In the present invention, the acrylic cationic electrodeposition paint obtained as described above is used to form an electrodeposition coating film to a predetermined thickness on the plated surface of a predetermined plated product. . The plated products on which this electrodeposited coating film is formed include all known products having a metal film on the surface of a predetermined base material. Therefore, as the base material, it is possible to use not only the metal itself but also ABS resin, other resins, or other materials, and the plating method used may be electrolytic plating or chemical plating. Of course, plated products obtained by any plating method can be used. That is, the present invention
Menki products obtained by either method, including electrolyzing a metal salt solution to deposit a metal film on a base material that is an electrode, or depositing a metal film on a base material by a chemical reaction, Applicable. Then, a coating film made of the acrylic cationic electrocoating paint according to the present invention is formed on such a plated product according to a conventional method, thereby making it possible to produce a plated product with excellent properties and high commercial value. be.

The acrylic cationic electrodeposited coating according to the present invention, which is formed on the plated surface of the plated product, will vary depending on the type of plated product, the type and thickness of the plated film, and the type of electrodeposition paint. Although it is difficult to determine the thickness appropriately and to limit it uniquely, it is generally formed to have a thickness of about 1 to 70 μm, preferably about 5 to 20 μm.

In addition, the acrylic cation type electrodeposition coating film formed on the plated surface of the plated product in this way can be coated by an appropriate method.
It is the same as the conventional method in that it is heated, hardened, and baked.

(Effects of the Invention) As described above, the acrylic cation type electrodeposited coating film formed on the plated surface of a plated product according to the present invention has excellent coating performance, good transparency of the coating film, and is also highly resistant to baking. It has excellent performance in terms of durability such as weather resistance, and does not cause the coating to yellow or become colored. While improving anti-corrosion properties, it is possible to provide a variety of color tones and construct a plated surface rich in design, and this is where the great industrial significance of the present invention resides.

(Examples) Some examples of the present invention will be shown below to clarify the present invention more specifically, but it is understood that the present invention is not limited in any way by the description of such examples. It goes without saying.

Furthermore, it should be understood that the present invention can be implemented in various forms other than the combinations or techniques illustrated in such embodiments. In addition, parts and percentages in the examples are as follows, unless otherwise specified.
All values are expressed on a weight basis.

Paint production example 1 10 parts of butyl cellosolve and 40 parts of isopropanol were added to a reactor equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer.
A mixture of the following composition was added dropwise from the dropping funnel at a reflux temperature of about 85° C. while stirring.

Blend amount (岨) Dimethylaminoethyl methacrylate 5dimethyl-2-
Hydroxypropylamine methacrylimide 15 Acrylic acid 2-
Hydroxyethyl 20 n-butyl acrylate
20 Styrene 15 2-ethylhexyl acrylate 5 Methyl methacrylate
20 Azobisisobutyronitrile
1 After dropping the above mixture, the reaction was continued for 3 hours at reflux temperature to obtain the desired acrylic copolymer solution (non-volatile components: 66.7%).

Next, 1 of the thus obtained acrylic copolymer solution
To 56 parts, 4 m (l) of IN-hydrochloric acid and 0.8 parts of acetic acid were added, and the mixture was stirred for about 1 hour to neutralize. Then, 839 parts of ion-exchanged water was added to the non-volatile components.
% cationic electrodeposition paint was obtained. The pH of the obtained cationic electrodeposition paint was 5.4.

Paint Production Comparison Example 1 In the above paint formulation example 1, 15 parts of dimethyl-2-hydroxypropylamine methacrylimide was not added, and instead, 10 parts of dimethylaminoethyl methacrylate was added.
Coating production example 1 using 30 parts of methyl methacrylate
The mixture was copolymerized according to the above procedure, further neutralized with hydrochloric acid and acetic acid, and then ion-exchanged water was added to prepare a cationic electrodeposition paint containing 10% of non-volatile components.

Paint production example 2 10 parts of butyl cellosolve and 40 parts of isopropanol were added to a reactor equipped with a stirrer, a cooling tube, a dropping funnel and a thermometer.
A mixture having the following composition was continuously added dropwise from the dropping funnel over a period of 3 hours while stirring at a reflux temperature of about 85°C.

Dimethylaminoethyl methacrylate 10 dimethyl-(
2-hydroxy-3-butoxypropyl)amine methacrylimide 25 2-hydroxyethyl acrylate
15 n-butyl acrylate 15 2-ethylhexyl acrylate 5 styrene
15 Methyl methacrylate
15 Azobisisobutyronitrile 1 After the dropwise addition of the blended mixture, 3
Continue the reaction for a period of time, and then add the desired acrylic copolymer solution (
Non-volatile components: 66.7%) were obtained.

Next, the thus obtained acrylic copolymer solution 15
After adding 2 parts of acetic acid to 6 parts and stirring for about 1 hour to effect neutralization, 842 parts of ion-exchanged water was added thereto to obtain a cationic electrodeposition paint containing 10% of non-volatile components. Note that the pH of the obtained cationic electrodeposition paint was 6.5.

Comparative Paint Production Example 2 In the above Paint Production Example 2, dimethyl-(2-hydroxy-3-butoxybropyl)amine methacrylimide 2
The desired acrylic copolymer solution was produced by increasing the amount of methyl methacrylate to 40 parts without adding 5 parts, and carrying out copolymerization according to the method of Paint Production Example 2. By performing the same operation as in Example 2, a cationic electrodeposition paint containing 10% of nonvolatile components was obtained.

Paint Production Example 3 Blocked isophorone diisocyanate (Block I) was added to 156 parts of the acrylic copolymer solution in Paint Production Example 1.
Add 33 parts of PDI), 10 parts of methyl isobutyl ketone and 23 parts of isopropanol, further add 1 part of IN=6 hydrochloric acid and 1 part of acetic acid, stir for about 1 hour to neutralize, and then add ion-exchanged water. 1,101 parts were added to obtain a cationic electrodeposition paint containing 10% of non-volatile components. Note that the pH of the obtained cationic electrodeposition paint was 5.5.

Comparative Paint Production Example 3 A predetermined cationic electrodeposition paint was produced according to the method of Paint Production Example 3 above, except that the acrylic copolymer thin liquid obtained in Comparative Paint Production Example 1 was used.

Paint Production Example 4 Acrylic copolymer solution 15 obtained in Paint Production Example 1
6 parts, fatty acid modified polyester (O1J value = 90) 1
0 parts, 6 parts of Quijirole, and 10 parts of butyl cellosolve, and further added 6 ml of IN-Salt H and 1 part of acetic acid to make about 1 part.
Neutralization was carried out by stirring for a period of time, and then 912 parts of ion-exchanged water was added to obtain a cationic electrodeposition paint containing 10% of non-volatile components. Note that the p and H values of the obtained cationic electrodeposition paint were 5.3.

Comparative Paint Production Example 4 A predetermined cationic electrodeposition paint was obtained in accordance with the method of Paint Production Example 4 above, except that the acrylic copolymer solution obtained in Comparative Paint Production Example 1 was used.

Example 1 A steel plate of 5 cm x IQ cm was plated with Ni according to a conventional method, and then plated with brass under the following conditions.

Plating bath composition Copper cyanide...27 g/l Zinc cyanide...9 g/4 Soda cyanide...56 g/7! Carbonated soda/
...30g/l Ammonia (28%)...2mβ/! Plating conditions pH...10.5 Temperature...45°C Da(A/dm2)...0.5Δ/dm" Time...
......1 min The brass color (Cu: 80
%, Zn: 20%) for a steel plate with a plated surface,
Each of the paints prepared in Paint Production Example 1 or Paint Production Comparative Example 1 was subjected to cathodic electrodeposition coating, then washed with water, drained with air spray, dried, and baked. In addition, the electrodeposition conditions are voltage:
3°V, time: 1 minute, bath temperature: 22°C, anode: carbon plate, distance between electrodes: 10cm, and the baking conditions were 175°C for 25 minutes in a hot air drying oven.

The appearance after baking was golden yellow, and no abnormalities were observed in the coating film.

For comparison, a sample electrodeposited using an anionic acrylic-melamine paint had a darkened color and bluish unevenness in parts, which significantly impaired the appearance.

Example 2 Ni-metalize a 6cm x 10cm brass plate using the usual method.

After that, grudge plating was applied under the following conditions.

Plating bath thread poisoned silver......40g/β Potassium cyanide...60g/1 potassium carbonate...50g/l Brightener... ...Appropriate amount plating conditions Temperature...30℃ Time...1m1n Dk (A/dm2)...7A/dm2 Then, this obtained The brass plate having a shiny silvery white plating layer was cathodic electrodeposited in the paint prepared in Paint Production Example 2 or Paint Production Comparative Example 2, and then washed and drained. After that, baking was performed. The electrodeposition conditions were: voltage: 40V, time: 21 minutes, bath temperature: 25°C, distance between electrodes: 15cm, and
The baking conditions were 175° C. for 30 minutes.

As a result, no discoloration was observed in any of the two types of plated products obtained. In addition, in the sample compared using the anionic acrylic-melamine paint, black discoloration was significant.

Example 3 Ni was applied to a 6cm x 10cm brass plate according to a conventional method.
After plating, black nickel plating was applied under the following conditions to obtain a glossy black plated brass plate.

Plating bath composition Nickel ammonium sulfate...60g/l zinc sulfate...
・・・・・・・・・ 8g/6 Sodium thiocyanate・
・・15g//! Plating conditions Temperature: 30℃ Time: 1 min Dw (A/dm”) 0.2 A/dm2
Next, the obtained black plated brass plate was subjected to cathode electrodeposition coating in the paint prepared in Paint Production Example 3 or Paint Production Comparative Example 3, respectively, and then washed with water, drained, and then baked in a prescribed manner. I did it. In addition, electrodeposition conditions,
The baking conditions were the same as those in Performance Test 1. Moreover, the baked coating films exhibited good appearance.

Example 4 Using a commercially available Bonderai +-m board measuring 7 cm x 15 cm, it was degreased and washed with water, and then subjected to cathode electrodeposition coating in the paint prepared in Paint Production Example 4 or Paint Production Comparative Example 4, respectively. After further washing and draining, a prescribed baking process was performed. The conditions for electrodeposition and baking are the same as in Example 1.
The conditions were similar.

For each coated board obtained in Examples 1 to 4 above, a pencil hardness test (JIS-5400),
Vertical peel test (JIS-5400), acetone immersion test (immersion in reagent grade 1 acetone at 25°C for 48 hours), boiling water test (immersion in distilled water at 100"C for 2 hours), salt water spray Test (J l5-H-8617)
72 hours, Cath test (J I 5-H-8617)
The test was carried out for 48 hours and the results are shown in Table 1 below.

As is clear from the results in Table 1, it is understood that all the coating films obtained using the acrylic cationic electrodeposition paint according to the present invention have excellent coating performance.

Claims (6)

[Claims] (1) (a) Structural formula below: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_1 is a hydrogen atom or a methyl group, and R_2
and R_3 are each an alkyl group having 1 to 4 carbon atoms, and R_4 is a hydrogen atom, an alkyl group, a hydroxyalkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkaryl group). (b) an ethylenically unsaturated monomer having an amino group; (c) one or two hydroxyalkyl or amide or amide derivatives of acrylic acid or methacrylic acid;
and (d) at least one α,β-ethylenically unsaturated monomer selected from the group consisting of alkyl esters of acrylic acid and methacrylic acid and aromatic vinyl monomers in a water-soluble organic solvent. The vinyl copolymer obtained by polymerization, or the vinyl copolymer mixed with a non-yellowing block isocyanate compound, or as necessary, the vinyl copolymer and/or the non-yellowing block isocyanate compound. An organic acid and/or mineral acid is added to a mixture containing a curing agent that reacts with a blocked isocyanate compound to neutralize the vinyl copolymer and make it water-soluble or water-dispersible. An acrylic cationic electrodeposition coating film is formed by forming an acrylic cationic electrodeposition coating film of a predetermined thickness on the plated surface of a predetermined plated product. Plated products with. (2) The vinyl copolymer contains 10 to 40% by weight of the monomer component (a) and 3% by weight of the monomer component (b).
~15% by weight and 10~40% of the component (c) monomer
The plated product according to claim 1, which is a copolymer containing % by weight, with the remainder consisting of the component (d) monomer, and has a weight average molecular weight of 5,000 to 60,000. (3) The non-yellowing block isocyanate compound is
Claim 1 or 2, which is an aliphatic or cycloaliphatic isocyanate compound having two or more isocyanate groups, wherein substantially all of the isocyanate groups are blocked with a blocking agent. plated products. (4) The curing agent is an acrylic-based, epoxy-based, alkyd-based, polyester-based, or polyol-based polyol resin containing a hydroxyl group, according to any one of claims 1 to 3. plated products. (5) Claims 1 to 4, wherein the curing agent is an amine or a polyamine compound having activated hydrogen.
Plated products described in any of the above. (6) The plated surface of the plated product is composed of plating of precious metals such as gold, silver, palladium, rhodium, ruthenium, or alloys thereof, or plating of nickel, copper, chromium, tin, zinc, or alloys thereof. A plated product according to any one of claims 1 to 5.